Year | Value | 2021 | 56.303 | 2020 | 56.757 | 2019 | 57.106 | 2018 | 56.587 | 2017 | 56.051 | 2016 | 55.39 | 2015 | 54.512 | 2014 | 52.903 | 2013 | 52.727 | 2012 | 52.059 | 2011 | 51.167 | 2010 | 50.534 | 2009 | 49.82 | 2008 | 49.088 | 2007 | 48.425 | 2006 | 47.83 | 2005 | 47.287 | 2004 | 46.855 | 2003 | 46.605 | 2002 | 46.459 | 2001 | 46.434 | 2000 | 46.587 | 1999 | 47.113 | 1998 | 47.557 | 1997 | 48.042 | 1996 | 48.632 | 1995 | 49.201 | 1994 | 49.742 | 1993 | 50.284 | 1992 | 50.737 | 1991 | 51.21 | 1990 | 51.584 | 1989 | 51.959 | 1988 | 52.2 | 1987 | 52.353 | 1986 | 52.416 | 1985 | 52.418 | 1984 | 52.349 | 1983 | 52.244 | 1982 | 52.071 | 1981 | 51.82 | 1980 | 51.51 | 1979 | 51.139 | 1978 | 50.697 | 1977 | 50.239 | 1976 | 49.743 | 1975 | 49.223 | 1974 | 48.69 | 1973 | 48.116 | 1972 | 47.535 | 1971 | 46.913 | 1970 | 46.289 | 1969 | 45.659 | 1968 | 44.999 | 1967 | 44.363 | 1966 | 43.727 | 1965 | 43.134 | 1964 | 42.557 | 1963 | 41.981 | 1962 | 41.492 | 1961 | 40.979 | 1960 | 40.488 |
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